Nuclear fuel reprocessing: Can pyro-processing reduce nuclear proliferation risk?

The long-term sustainability of nuclear energy requires a closed fuel cycle in which used fuel is reprocessed and recycled. Unlike the PUREX process, which produces a pure plutonium product, pyro-processing produces a depleted uranium ingot and a mixed ingot of depleted uranium and transuranic elements (neptunium, plutonium, americium, and curium) in the ratio 1:1. This seems to suggest that pyro-processing has a lower nuclear proliferation risk compared to PUREX because of the non-availability of a pure Pu product in pyro-processing. In this paper, we study some of the technical challenges in safeguarding a pyro-processing facility with respect to various special nuclear material (SNM) diversion scenarios and propose some possible solutions. We also analyze the misuse of pyro-processing in tandem with a covert PUREX facility. Wide-area environmental sampling and satellite imagery could detect the misuse. Additional strategies recommended are: employment of resident inspectors, establishment of dedicated nuclear safeguards funds, and international sanctions against the misuse of pyro-processing facilities. Results of the study show that suggested technical and administrative measures can make SNM diversion from a pyro-processing facility extremely difficult. We conclude that the use of pyroprocessing in place of PUREX in a closed fuel cycle can lower the proliferation risk.